The world’s first weed-friendly gym is opening this fall in San Francisco.

Power Plant Fitness will assess its members to determine how to best incorporate cannabis into their sweat sessions — whether they should vape, consume an edible or smoke up pre- or post-workout.

The gym’s co-founder Jim McAlpine previously started the 420 Games, an annual sports event for athletic tokers. He wants to break the stereotype that marijuana users are just a bunch of couch potatoes.

“I think sports will become one of the bigger pieces of the marijuana industry,” McAlpine told SFGate.com. “Marijuana, if you use it in a responsible way, accentuates the parts of sports that you love and helps you to do them better.”

McAlpine isn’t the only advocate for exercising under the influence. Medical marijuana has been shown to alleviate pain and improve moods, and weed activists like McGill University professor Mark Ware say the plant benefits fitness enthusiasts.

“It may help some athletes get into a zone and put their bodies through very tough physical activity,” Ware, executive director of the Canadian Consortium for the Investigation of Cannabinoids, told Men’s Journal. “It may enable them to focus on those repetitive tasks.”

But rolling up a joint before your workout could have its downsides, too. A recent study found that men who took THC, a main ingredient in marijuana, had slower reaction times.

“What research we have is anecdotal,” Iñigo San Millán, director of the Human Performance Lab at the University of Colorado, told Men’s Journal. “We know it might help with inflammation, sleep, and pain relief. But we don’t know if it will improve performance — or if it might even jeopardize it.”